Question

energy in most ecosystems must flow through autotrophs because
a. only autotrophs can convert solar energy into chemical energy
b. autotrophs are simpler organisms than heterotrophs
c. heterotrophs only generate a small fraction of their energy from photosynthesis
d. all of the above

Explanation:

• Autotrophs, like plants, perform photosynthesis. They convert solar energy (from sunlight) into chemical energy (glucose). This is the base of the energy flow in most ecosystems.
• Heterotrophs (e.g., animals) cannot perform photosynthesis. They rely on consuming other organisms (either autotrophs or other heterotrophs) for energy. So, energy must first pass through autotrophs as they are the primary producers that capture solar energy.
• Option b is incorrect as autotrophs are not necessarily simpler (e.g., trees are autotrophs and are complex organisms). Option c is incorrect as heterotrophs do not perform photosynthesis at all (except for some very rare exceptions that are not the norm for most ecosystems considered in basic ecology).

Answer:

A. only autotrophs can convert solar energy into chemical energy